1. Field of the Invention
The present invention relates to a linear compressor, and, more particularly, to a linear compressor in which a spring seat, for use in the fixation of a supporting spring, is provided with a buffer to prevent vibration generated in the spring seat from being transmitted to a shell, thereby eliminating noise discharge to the outside of the linear compressor.
2. Description of the Related Art
Generally, a linear compressor is an apparatus to suction and compress fluid, such as gaseous fluid (hereinafter, referred to as fluid) while linearly reciprocating a piston inside a cylinder using a linear driving force of a linear motor to thereby discharge the compressed fluid.
FIG. 1 is a longitudinal sectional view of a conventional linear compressor.
As shown in FIG. 1, the conventional linear compressor includes a shell 2, and a linear compression unit 4 arranged in the shell 2 to compress fluid.
A fluid suction pipe 6 is penetrated through one side of the shell 2, and a fluid discharge pipe 8 is also penetrated through the other side of the shell 2.
The linear compression unit 4 includes a cylinder block 12 centrally provided with a cylinder 10, a back cover 16 having a fluid suction port 14, a piston 18 inserted in the cylinder 10 to be linearly reciprocated inside the cylinder 10, a linear motor 20 to generate a driving force required to linearly reciprocate the piston 18 inside the cylinder 10, and a discharge unit 30 provided at a front side of the cylinder 10 to discharge compressed fluid from the cylinder 10.
The linear motor 20 is basically comprised of a stator and a mover. The stator includes an outer stator 21, an inner stator 22, a bobbin 23 mounted in the outer stator 21, and a coil 24 wound around the bobbin 23 to produce a magnetic field. The mover includes a magnet 25 to be linearly reciprocated using a magnetic force generated in the vicinity of the coil 24, and a magnet frame 26 to support the magnet 25 mounted thereon.
The piston 18 is affixed to the magnet frame 26 to receive a linear movement force of the magnet 25. The piston 18 is formed at a rear end thereof with a flange portion 28 to be affixed to a front surface of the magnet frame 26.
The linear compressor further comprises main springs to elastically support the piston 18 when the piston is linearly reciprocated. The main springs include a first main spring 34 interposed between the back cover 16 and a spring support 32 affixed to a rear surface of the magnet frame 26, and a second main spring 38 interposed between the spring support 32 and a stator cover 36 affixed to a rear end of the outer stator 21.
A plurality of supporting springs 40 are mounted between the shell 2 and the linear compression unit 4 to support the linear compression unit 4 in a shock-absorbing manner.
The supporting springs 40 include a first supporting spring 41 interposed between the cylinder block 12 and the shell 2, and a second supporting spring 42 interposed between the spring support 32 and the shell 2.
Each of the first and second supporting springs 41 and 42 has a first end fitted into a first spring seat 43 mounted at the shell 2, and a second end fitted into a second spring seat 44 mounted at the cylinder block 12 or spring support 32.
Now, operation of the conventional linear compressor configured as stated above will be explained.
First, when the linear motor 20 is operated, the magnet 25 is linearly reciprocated to transmit a linear reciprocating movement force to the piston 18 by way of the magnet frame 26. Thereby, the piston 18 is linearly reciprocated inside the cylinder 10.
According to the linear reciprocating movement of the piston 18, fluid present inside the shell 2 is introduced into the cylinder 10 through the fluid suction port 14 of the back cover 16 to thereby be compressed in the cylinder 10 by means of the piston 18. After that, the compressed fluid is discharged to the outside of the shell 2 through the discharge unit 30 and the discharge pipe 8.
In operation, the first and second supporting springs 41 and 42 serve to absorb vibration generated in the linear compression unit 4.
This prevents the vibration of the linear compression unit 4 from being transmitted to the shell 2, eliminating noise generation of the linear compressor.
However, in the case of the conventional linear compressor, since both ends of the supporting springs 40 are fitted into the first and second spring seats 43 and 44, it shows relative movement between the supporting springs 40 and the first and second spring seats 43 and 44 upon intensive operation of the linear compression unit 4, causing frictional vibration relative to each other. Consequently, the frictional vibration is transmitted to the shell 2, resulting in discharge of high-frequency noise to the outside of the linear compressor.